REPAIR OCCUPANCY (Repair reporting occupancy for storage pool)

zz71 zz63 REPAIR OCCUPANCY QUERY OCCUPANCY

Technote (troubleshooting)

Problem(Abstract)

In Tivoli Storage Manager server version 6.x, the cluster records that are used to track occupancy values for a given node may become invalidated such that occupancy values being reported are inaccurate. One result of this problem could be seen in the Query OCCupancy command where the Physical and Logical Space Occupied values are incorrect. Also, the Query STGpool F=D could show an incorrect value for Duplicate Data Not Stored.

Cause

This could be caused during data movement of deleted deduplicated chunks. The Tivoli Storage Manager would add the occupancy of the deleted chunks to the nodes occupancy making the total occupancy invalid. Once the chunk has been deleted it should no longer count towards the overall occupancy. This issue would cause the storage pool to grow from a reporting perspective until deduplication would no longer show proper results. Another cause could be client side deduplication enabled. This would only cause the number of files being reported to be wrong as opposed to the sizing.

Resolving the problem

This utility is primarily intended to correct file and/or chunk mismatches in the QUERY OCCUPANCY output. If there are small discrepancies with the SIZE values, this utility may or may not have an impact with the results.

Resolving the problem requires upgrading to at least 6.1.5.102, 6.2.3.100 or 6.3.0.0 of the Tivoli Storage Manager. These released levels not only contain the fix from APAR IC73005, but also the utility for fixing the reporting occupancy.

The utility added to Tivoli Storage Manager is called REPAIR OCCUPANCY. This command takes 3 parameters:

storage_pool_name (Required) Specifies the name of the storage pool to be fixed. This parameter is required for the utility to work.

node_name (Required) Specifies the name of the client node. The use of wildcards is not acceptable for this command.

FIX Specifies how the server is to resolve the inconsistencies with the reporting occupancy for the storage pool in question. This parameter is optional. The default is NO.

FIX=No Tivoli Storage Manager will only report the reported occupancy values and the actual values that will replace the reporting values. These values will not be updated at this time though.

FIX=Yes The server will fix any inconsistencies found for the reporting logical occupancy.

Example: Show the current reporting values and what the actual reporting values should be for the requested storage pool
Using the REPAIR OCCUPANCY with the parameter FIX=No will display the current reporting values and what the values will be updated to once the command is ran with FIX=Yes.

Example: Repair the reporting values for the storage pool
Using the REPAIR OCCUPANCY command with FIX=Yes will look similar to FIX=No but the exception will be additional messaging stating the changes were made.